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arXiv:2609.07892

Few-Body Decay Dynamics in Colloidal CsPbI3 Quantum-Dot Clusters

Emma Daggett, Christian M. Lange, Nicholas Favate, Ankit Kundu, Ishita Agarwal, Arya D. Keni, Adhyyan S. Mansukhani, Christina W. Li, Libai Huang, Jonathan D. Hood

quant-phSubmitted Sep 7, 2026• Announced Sep 9, 2026

Abstract

Colloidal perovskite quantum dots combine bright emission with the ability to self- assemble into closely spaced structures, enabling radiative dynamics to be studied from isolated emitters to few-dot clusters. Here, we characterize CsPbI3 perovskite quan- tum dots from isolated emitters to self-assembled clusters containing up to ten dots. We estimate the number of emitters in each cluster using a combination of photon autocorrelation, blinking statistics, and emission brightness. Compared with isolated dots, clusters containing two or more emitters exhibit biexponential decay, with a short lifetime that decreases with emitter number and an additional long-lived component. Photon-correlation Fourier spectroscopy shows that the single-dot emission remains far from the lifetime-limited regime. Nevertheless, we observe emitter-number-dependent decay dynamics even in this low-coherence regime. Together, these measurements es- tablish self-assembled perovskite quantum-dot clusters as a platform for studying how collective optical behavior emerges between the single-emitter and ensemble limits

Comments: 26 pages (9 page main, 13 page supplemental, 4 page references), 4 main figures, 5 supplemental figures

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